1. Field of the Invention
The present invention relates to a reduction printing apparatus in a desk-publishing system using a personal computer, particularly, it relates to a reduction printing apparatus for binary images extended on a bit-map.
2. Description of the Related Art
Recently, a desk-top-publishing (DTP) system using a personal computer is widely utilized in the newspaper industry for editing and preparing publications using a personal computer. That is, on the display of the personal computer, an editor inputs characters, drafts drawings, edits pages, performs a layout for space, and finally prepares a block copy that is printable.
In such a high-speed DTP system, high-speed peripheral apparatuses are also required. Particularly, an output apparatus that prints the result of the edition is required. Recently, laser printers, which are widely utilized, satisfy the requirements of the DTP system from the view point of high speed and high quality.
For example, in the newspaper industry, to simultaneously publish a newspaper having the same content in central and local districts, one manuscript is simultaneously sent from the central district to the local districts. In this case, there are various output apparatuses each having different resolution in the local districts. For example, the manuscript is sent from the central district to output apparatuses of the local district, for example, laser printers having high resolution (for example, 400 dpi) or facsimile apparatuses having low resolution (for example, 200 dpi).
As a counter-measure for such various output apparatuses each having different resolution, reduced printing is performed by a thinned-out operation for an original image in accordance with the resolution of the output apparatus. In this case, it is important to avoid the deterioration of the quality of the image caused by the thinned-out operation.